The invention relates generally to marine propulsion devices such as outboard motors and stern drive units. More specifically, the invention relates to a marine propulsion device having a lower unit with a propeller located below a cavitation plate, which lower unit includes an exhaust outlet for discharging exhaust gas below the cavitation plate. Prior marine propulsion devices are disclosed in Larsen U.S. Pat. No. 3,198,162, issued Aug. 3,1965; Boda U.S. Pat. No. 3,350,879, issued Nov. 7, 1967; and Irgens U.S. Pat. No. 3,249,083, issued May 3, 1966.